DESCRIPTION (provided by applicant: Assessment and monitoring of the viral load of HIV+ patients and their adherence to antiretroviral (ART) therapy are critically important for controllig the course of the disease, assessing transmission risks, and monitoring of HIV infection within communities. Viral load measurements are currently conducted in laboratory settings using costly and bulky apparatus including benchtop optical microscopes and sample preparation steps that require advanced lab instruments, which are hard to find and operate in resource limited environments or at the patient's home. In addition to the complexity, cost and bulkiness of existing tools, HIV viral load measurement methods currently rely on blood drawing, which can in general create significant sanitary and safety concerns in resource limited settings or at home. The proposed research plan covers the development and testing of a field-portable and label-free flexible sensing platform that is based on surface plasmon resonant (SPR) properties of specially designed quasi three-dimensional metal nanostructures (MNS) which will be integrated with commercially available soft contact lenses to create a cost effective and non-invasive diagnostic tool that can work even at home for measuring the viral load of HIV+ patients using tear. This new sensing platform will be designed to achieve flexibility by constructing its sensing unit on flexible substrates to enable intimate, direct contact with curved or irregular surfaces such as the human eye without any additional sample retrieval or processing steps and without obscuring natural vision or causing user discomfort. In addition to the flexible plasmonic sensor integrated onto the contact lens surface, we will also create a field portable and cost- effective smart phone based spectral reader platform to specifically analyze and quantify the viral load through multi-spectral imaging and automated analysis of the built-in nano-sensor on the surface of each contact lens. Previous studies have shown that HIV particles exist in tear and ocular fluids of HIV+ patients, and therefore tracking HIV status through tear can present a much safer and simpler approach for monitoring of HIV+ patients and their adherence to ART. In addition to improving care adherence and non- invasively quantifying the viral load of HIV+ patients through tear films, this proposed platform will ultimately provide a simple, cost-effective and light-weight toolset for multiplexed biological and chemical sensing needs, enabling various other future biomedical applications of wearable sensors.